• Journal of Life Science
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• v.26 no.6
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• pp.698-704
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• 2016

The intracellular transport of organelles and protein complexes is mediated by kinesin superfamily proteins (KIFs). The first kinesin, kinesin 1, was identified as a molecular motor protein that moves various organelles and protein complexes along the microtubule rails in cells. Kinesin 1 is a tetramer of two heavy chains (KHCs, also called KIF5s) and two kinesin light chains (KLCs). KIF5s interact with many different proteins through their tail region, but their binding proteins have not yet been fully identified. To identify the interaction proteins for KIF5A, we performed yeast two-hybrid screening and found a specific interaction with ferritin heavy chain (Frt-h), which has a role in iron storage and detoxification. Frt-h bound to the amino acid residues between 800 and 940 of KIF5A and to other KIF5s in the yeast two-hybrid assay. The coiled-coil domain of Frt-h is essential for interaction with KIF5A. In addition, ferritin light chain (Frt-l) interacted with KIF5s in the yeast two-hybrid assay. In addition, these proteins showed specific interactions in the glutathione S-transferase (GST) pull-down assay. An antibody to KHC specifically co-immunoprecipitated Frt-h and Frt-l from mouse brain extracts. These results suggest the kinesin 1 motor protein may transport the ferritin complex in cells.

• Journal of Life Science
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• v.29 no.3
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• pp.369-375
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• 2019

Microtubules form through the polymerization of ${\alpha}-$ and ${\beta}-tubulin$, and tubulin transport plays an important role in defining the rate of microtubule growth inside cellular appendages, such as the cilia and flagella. Heterotrimeric kinesin 2 is a molecular motor member of the kinesin superfamily (KIF) that moves along the microtubules to transport multiple cargoes. It consists of two motor subunits (KIF3A and KIF3B) and a kinesin-associated protein 3 (KAP3), forming a heterotrimeric complex. Heterotrimeric kinesin 2 interacts with many different binding proteins through the cargo-binding domains of the KIF3s, but these binding proteins have not yet been specified. To identify these proteins for KIF3A, we performed yeast two-hybrid (Y2H) screening and found a specific interaction with ${\beta}2-tubulin$ (Tubb2), a microtubule component. Tubb2 was found to bind to the cargo-binding domain of KIF3A but did not interact with KIF3B, KIF5B, or kinesin light chain 1 in the Y2H assay. The carboxyl-terminal region of Tubb2 is essential for interaction with KIF3A. Other Tubb isoforms, including Tubb1, Tubb3, Tubb4, and Tubb5, also interacted with KIF3A in the Y2H screening. However, ${\alpha}1-tubulin$ (Tuba1) did not interact with KIF3A. In addition, an antibody to KIF3A specifically co-immunoprecipitated the KIF3B and KAP3 associated with Tubb2 from mouse brain extracts. In combination, these results suggest that a heterotrimeric kinesin 2 motor protein is capable of binding to tubulin and may transport it in cells.

• Journal of Microbiology
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• v.45 no.2
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• pp.158-167
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• 2007

In this study, we have cloned a novel cDNA encoding for a papain-family cysteine protease from the Uni-ZAP XR cDNA library of the polychaete, Periserrula leucophryna. This gene was expressed in Escherichia coli using the T7 promoter system, and the protease was characterized after partial purification. First, the partial DNA fragment (498 bp) was amplified from the total RNA via RT-PCR using degenerated primers derived from the conserved region of cysteine protease. The full-length cDNA of cysteine protease (PLCP) was prepared via the screening of the Uni-ZAP XR cDNA library using the $^{32}P-labeled$ partial DNA fragment. As a result, the PLCP gene was determined to consist of a 2591 bp nucleotide sequence (CDS: 173-1024 bp) which encodes for a 283-amino acid polypeptide, which is itself composed of an 59-residue signal sequence, a 6-residue propeptide, a 218-residue mature protein, and a long 3'-noncoding region encompassing 1564 bp. The predicted molecular weights of the preproprotein and the mature protein were calculated as 31.8 kDa and 25 kDa, respectively. The results of sequence analysis and alignment revealed a significant degree of sequence similarity with other eukaryotic cysteine proteases, including the conserved catalytic triad of the $Cys^{90},\;His^{226},\;and\;Asn^{250}$ residues which characterize the C1 family of papain-like cysteine protease. The nucleotide and amino acid sequences of the novel gene were deposited into the GenBank database under the accession numbers, AY390282 and AAR27011, respectively. The results of Northern blot analysis revealed the 2.5 kb size of the transcript and ubiquitous expression throughout the entirety of the body, head, gut, and skin, which suggested that the PLCP may be grouped within the cathepsin F-like proteases. The region encoding for the mature form of the protease was then subcloned into the pT7-7 expression vector following PCR amplification using the designed primers, including the initiation and termination codons. The recombinant cysteine proteases were generated in a range of 6.3 % to 12.5 % of the total cell proteins in the E. coli BL21(DE3) strain for 8 transformants. The results of SDS-PAGE and Western blot analysis indicated that a cysteine protease of approximately 25 kDa (mature form) was generated. The optimal pH and temperature of the enzyme were determined to be approximately 9.5 and $35^{\circ}C$, respectively, thereby indicating that the cysteine protease is a member of the alkaline protease group. The evaluation of substrate specificity indicated that the purified protease was more active towards Arg-X or Lys-X and did not efficiently cleave the substrates with non-polar amino acids at the P1 site. The PLCP evidenced fibrinolytic activity on the plasminogen-free fibrin plate test.

• Journal of Life Science
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• v.21 no.10
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• pp.1434-1442
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• 2011

A genetic variation within 29 strains of F. velutipes was analyzed by internal transcribed spacer (ITS) sequence analysis and random amplified polymorphic DNA (RAPD). Seven hundred and twenty base pairs were sequenced during the analysis of the ITS region, but no significant variation was observed among the 29 strains of F. velutipes. Sixteen out of 40 random primers amplified polymorphic RAPD fragment patterns. The polymorphic levels of RAPD bands by some primers (OPA-2,4,3,9,10,20) were very high in all 29 strains, with 3,030 fragments ranging between 200 and 2,000 bp. Intraspecific genetic dissimilarity of the 29 strains was calculated to range from 3.3% to 45% by Nei-Li's method using these 3,030 RAPD bands. The genetic variation among Korean strains was relatively high, with dissimilarities ranging between 17% and 38.6%. In the Neighbor-Joining analysis using the genetic dissimilarities based on RAPD, all 29 strains were classified into 5 clusters. Strains in each cluster showed specific characteristics according to their origin and strains. These results suggested that OPA and OPB primers could be used for developing molecular genetic markers and screening of unidentified (F. velutipes) strains.

• IMMUNE NETWORK
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• v.1 no.1
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• pp.77-86
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• 2001

Background: Hepatitis C virus(HCV), a family of Flaviviridae, has a host cell-derived envelope containing a positive-stranded RNA genome, and has been known as the maj or etiological agent for chronic hepatitis, hepatic cirrhosis, and hepatocellular carcinoma. There remains a need to dissect a molecular mechanism of pathogenesis for the development of therapeutic and effective preventive measure for HCV. Identification of cellular receptor is of central importance not only to understand the viral pathogenesis, but also to exploit strategies for prevention of HCV. This study was aimed at identifying peptide mimotopes inhibiting the binding of E2 protein of HCV to MOLT-4 cell. Methods: In this study, phage peptide library displaying a random peptides consisting of 7 or 12 random peptides was employed in order to pan against E2 protein. Free HCV particles were separated from the immune complex forms by immunoprecipitation using anti-human IgG antibody, and used for HCV-capture ELISA. To identify the peptides inhibiting E2-binding to MOLT-4 cells, E2 protein was subj ect to bind to MOLT-4 cells under the competition with phage peptides. Results: Several phage peptides were selected for their specific binding to E2 protein, which showed the conserved sequence of SHFWRAP from 3 different peptide sequences. They were also able to recognize the HCV particles in the sera of HCV patients captured by monoclonal antibody against E2 protein. Two of them, showing peptide sequence of HLGPWMSHWFQR and WAPPLERSSLFY respectively, were revealed to inhibit the binding of E2 protein to MOLT-4 cell efficiently in dose dependent mode. However, few membrane-associated receptor candidates were seen using Fasta3 programe for homology search with these peptides. Conclusion: Phage peptides containing HLGPWMSHWFQR and WAPPLERSSLFY respectively, showed the inhibition of E2-binding to MOLT-4 cells. However, they did not reveal any homologues to cellular receptors from GenBank database. In further study, cellular receptor could be identified through the screening of cDNA library from MOLT-4 or hepatocytes using antibodies against these peptide mimotopes.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.60 no.3
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• pp.293-299
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• 2015

High temperature is one of major environmental stress. Heat tolerance managing is difficult through the phenotypic selection, so marker assistant selection (MAS) using molecular markers like as RAPD, SSR etc. was tried to select useful traits for heat tolerance. Fourteen SSR markers reported by previous research were selected for this research. We tried to evaluate 14 SSR markers for MAS using 31 useful wheat resources including 24 crossing line from Turkey, six Korean wheat cultivars and Chinese spring. The average of the number of alleles and PIC values in this study were 6.14 and 0.64, respectively. Two major clades and four sub clades were grouped by phylogenetic tree using UPGMA. Four Korean wheat cultivars were distinct from other Turkey resources in the phylogenetic dendrogram. From the results, we expected that these markers were able to adapt to screening wheat genotyping for heat tolerance.

• Nuclear Medicine and Molecular Imaging
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• v.41 no.3
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• pp.185-193
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• 2007

This review focuses on the use of $^{18}F-FDG$ PET/CT to evaluate second primary cancers. The emergence of a second primary cancer is an important prognostic factor in cancer patients. The early detection of a second primary cancer and the appropriate treatment are essential for reducing the morbidity and mortality associated with these tumors. Integrated $^{18}F-FDG$ PET/CT, which can provide both the metabolic and anatomic information of a cancer, has been shown to have a better accuracy in oncology than either CT or conventional PET. The whole body coverage and high sensitivity of $^{18}F-FDG$ PET/CT along with its ability to provide both metabolic and anatomic information of a cancer make it suitable for evaluating a second primary cancer in oncology. Whole body $^{18}F-FDG$ PET/CT is useful for screening second primary cancers with a high sensitivity and good positive predictive value. In order to rule out the presence of a second primary cancer or an unexpected metastasis, further diagnostic work-up is essential when abnormal findings indicative of a second primary cancer are found on the PET/CT images. PET/CT is better in detecting a second primary tumor than conventional PET.

• Biomedical Science Letters
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• v.12 no.2
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• pp.73-79
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• 2006

Nebulin is a giant ($600{\sim}900$ kDa), modular sarcomeric protein proposed to regulate the assembly, and to specify the precise lengths of actin filamints in vertebrate skeletal muscles. Recently, There is an evidence that the nebulin also expressed in non muscle tissue, brain and liver. We identified a new isoform of nebulin from adult brain library by PCR screening. It contains two simple-repeats exon 165, 166 and linker-repeats exon $154{\sim}161$ except exon 159. The nebulin modules M160 to M170 (exon 150 to exon 161) has been shown to bind desmin. In mature striated muscle, desmin intermediate filaments surround Z-discs and link individual myofibrils laterally at their Z-discs and to other intracellular structures, including the costameres and the intercalated discs of the sarcolemma, sarcoplasmic reticulum, mitochondria, T-tubules, and nuclei. Therefore, it is an interesting possibility that the differential splice pathways within the linker region of nebulin modify the affinity of nebulin's interaction with desmin. The specific interactions of nebulin and desmin were confirmed in vivo by yeast two hybrid experiments. To verify in the cellular level the interaction between nebulin isoform and desmin, we transfected COS-7 cell with EGFP-tagged nebulin and DsRed-tagged desmin. Based on evidence showing that despite exon 159 was deleted, the new isoform of nebulin was interact with desmin. This suggest that nebulin in brain may interact with another intermediate filament. The conservation of these ligand-binding capacity in brain and skeletal nebulins suggest that nebulins may have conserved roles in brain and skeletal muscle.

• Journal of Microbiology
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• v.44 no.1
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• pp.54-63
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• 2006

Ferritin is a major eukaryotic protein and in humans is the protein of iron storage. A partial gene fragment of ferritin (255 bp) taken from the total RNA of Periserrula leucophryna, was amplified by RT-PCR using oligonucleotide primers designed from the conserved metal binding domain of eukaryotic ferritin and confirmed by DNA sequencing. Using the $^{32}P-labeled$ partial ferritin cDNA fragment, 28 different clones were obtained by the screening of the P. leucophryna cDNA library prepared in the Uni-ZAP XR vector, sequenced and characterized. The longest clone was named the PLF (Periserrula leucophryna ferritin) gene and the nucleotide and amino acid sequences of this novel gene were deposited in the GenBank databases with accession numbers DQ207752 and ABA55730, respectively. The entire cDNA of PLF clone was 1109 bp (CDS: 129-653), including a coding nucleotide sequence of 525 bp, a 5' -untranslated region of 128 bp, and a 3'-noncoding region of 456 bp. The 5'-UTR contains a putative iron responsive element (IRE) sequence. Ferritin has an open reading frame encoding a polypeptide of 174 amino acids including a hydrophobic signal peptide of 17 amino acids. The predicted molecular weights of the immature and mature ferritin were calculated to be 20.3 kDa and 18.2 kDa, respectively. The region encoding the mature ferritin was subcloned into the pT7-7 expression vector after PCR amplification using the designed primers and included the initiation and termination codons; the recombinant clones were expressed in E. coli BL21(DE3) or E. coli BL21(DE3)pLysE. SDS-PAGE and western blot analysis showed that a ferritin of approximately 18 kDa (mature form) was produced and that by iron staining in native PAGE, it is likely that the recombinant ferritin is correctly folded and assembled into a homopolymer composed of a single subunit.

• Development and Reproduction
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• v.8 no.1
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• pp.1-9
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• 2004

The potential importance of proteomic approaches has been clearly demonstrated in other fields of human medical research, including liver and heart disease and certain forms of cancer. However, reproductive researches have been applied to proteomics poorly. Proteomics can be defined as the systematic analysis of proteins for their identity, quantity, and function. It could increase the predictability of early drug development and identify non-invasive biomarkers of toxicity or efficacy. Proteome analysis is most commonly accomplished by the combination of two-dimensional gel electrophoresis(2DE) and MALDI-TOF(matrix-assisted laser desorption ionization-time of flight) MS(mass spectrometry) or protein chip array and SELDI-TOF(surface-enhanced laser desorption ionization-time of flight) MS. In addition understanding the possessing knowledge of the developing biomarkers used to assess reproductive biology will also be essential components relevant to the topic of reproduction. The continued integration of proteomic and genomic data will have a fundamental impact on our understanding of the normal functioning of cells and organisms and will give insights into complex cellular processes and disease and provides new opportunities for the development of diagnostics and therapeutics. The challenge to researchers in the field of reproduction is to harness this new technology as well as others that are available to a greater extent than at present as they have considerable potential to greatly improve our understanding of the molecular aspects of reproduction both in health and disease.